The objectives of the proposed research are to study the mechanisms and regulation of neurotransmitter metabolism in the mammalian central nervous system. The biochemistry of the uptake, storage and release of the postulated neurotransmitters including GABA (gamma-aminobutyric acid), glutamate, and aspartate will be studied. The role of Na ion (and Na ion gradient), K ion (and K ion gradient) and Ca2 ion on these processes will be examined. Furthermore, studies on the enzymology of bovine brain cAMP-dependent protein kinase will be performed. The mechanisms of enzyme inhibition by guanidinium compounds and by Cibachron Blue F3GA will be investigated. The purpose of these studies is to learn the mechanism whereby the regulatory subunit inhibits the catalytic subunit activity of the holoenzyme.